Mentos eruption

Friday 29th May 2015

I've seen some great Mentos and Diet Coke eruption videos on Youtube, and I've always wondered whether other soft drinks work too.

Here comes the science.

Hypothesis

The Mentos eruption works just as well with any kind of soft drink, but it doesn't work with Fruit Mentos or sparkling water. It will be more explosive with powdered Mentos because of the increased surface area.

Method

12 bottles of various soft drinks and 12 packets of Mentos were bought from a local supermarket. The bottles were opened and a packet of Mentos (eight sweets) was dropped into the bottle using our patented delivery mechanism (an empty Berocca tube).

Results

Screenshots were taken from the video at peak foam. The images were scaled to make the bottles the same size and the eruptions were plotted on a pretty graph.

The average heights of the eruptions were calculated. Note that Coke Life and sparkling water were not included in either of the diet or regular averages.

Average height: 26cm

Average diet drink height: 26cm

Average sugary drink height: 34cm

Average Tesco drink height: 32cm

Average Coca-Cola drink height: 28cm

Conclusion

Our experiment shows that soft drinks containing sugar can produce higher eruptions than diet products, and that it does work with Fruit Mentos but not with sparkling water. Powdered Mentos do not produce a higher plume than whole sweets.

Sadly our delivery mechanism left a lot to be desired, and to be honest the height of the eruption a lot to do with how many Mentos were delivered into the bottle before it started foaming.

Wikipedia explains the science behind it. The world record for the most number of simultaneous Mentos and Soda fountains is 4,334 bottles at once!